The Trollshaws were the wooded, hilly country east of the river Hoarwell in Eriador, a wild and ill-reputed land through which the road to Rivendell passed. There, in an earlier age, Bilbo and Thorin's company were waylaid by three trolls -- Tom, Bert, and William -- and were saved only when Gandalf, mimicking their voices in the dark, kept them quarrelling until the sun rose and turned them to stone. The petrified trolls still stood in a clearing when Frodo's company passed by years afterward.